Don't be too sure.
I got quite a few friends who use 300D and aiming for L lens and said they will never upgrade their camera after getting L.
Few months later after having purchase L, they asked me whether they should go for 20D or 10D.
Now their camera are even better than mine . lol
We will wait and see loh. By that time if you happen to ask me that question, I will say 5D . lol